Furnace



Dem-Z3, 1924. 1,520,096 I A. E. STRE DWICK' FURNACE Filed May 17, 1922 Patented Dec. 23, 19.2

earner AUBREY EDWARD STR'EADW'IOK, OF TORONTO, ONTARIO, CANADA, ASSIGNO-R TO- STREAIDWICK HEAT AND VENTILATING SYSTEM LIMITED, OF TORONTO, ONTARIO,

CANADA.

FURNACE.

Application filed May 17, 1922. Serial No, 561,743.

1" 0 all whom-z't'mag concern:

Be it known that I, AUBREY EnwARD' STREADWICK, of the city of Toronto, in the county of York, Province of Ontario Canada, a sub ect of the Kmg of. Great Britain, have invented certain new and use- 1 and which is particularly adapted for use as a combined hot water and hot air heater.

I attain my object by means of the constructions hereinafter described and illus trated in the accompanying drawings in which Fig. 1 is a front elevationpartly. in section of my improved furnace;

Fig. 2- a side elevation partly in section;

Fig. 3 a rear elevation of the fire box and combustion chamber; and

Fig. 4C a plan view of the same,

In the drawings like numerals of reference indicates corresponding parts in the different figures.

1 is a furnace casing of ordinary construction provided with the usual ash pit door 2, clinker door 3,.fuel. door 10, and a cleanout door 41- near the top. A smoke flue 5 extends through the top of the casing and communicates with the interior of the easing. An annular damper 6 is adapted to control apertures in the depending end of the smoke flue so that the products of combustion may be either caused to pass down and then up through the open lower end of the fine or allowed to travel directly along under. the top of the casing and through the apertures in the side of the smoke flue. This damper is controlled by the pull rod 7 extending to the outside of the furnace.

To increase the heating surface of the top of the furnace I form therein a plurality of pyramidal pots 8 open at the under side. These pots extend up into the air space of an air jacket 9 which entirely surrounds the casing 1 above the ashpit portion thereof. This casing fits about the fuel door and clean out door in the usual manner.

11 is the cold air inlet to the air jacket and from its top extend one or more air fiues 12 in the usual manner. A water pan 13 is also adaptedto pass throughan opening in the top :of the air jacket to provide moisture for the air therein.

.Animportant part-of'my invention lies in the constructionlof the firebox and combustion chamber of the furnace. The firebox and combustion chamber are of rectangular form and are formed of tubes which are closely spaced in the firepot and more widely spaced in the walls and top of the combustion chamber, the front of the combustion chamber being open for the passlage of fuel thrown in through the fuel coor.v I

While diff rent arrangements of the tubes are possible to secure the results I aim at, there are certain fundamental. requirements which must be fulfilled. As through these tubes flowsthe waterto be heated, to ensure proper circulation it is important that the flow shall be horizontally and upwardly and nev'er'at any point downwardly. It is also advantageous to'elimina-te pipe fittings in the connection of the tubes, as otherwise great difliculty is experienced in securing the necessary heating surfacefand in securing the close spacing of the tubes desirable in the firepot. I v

I therefore form the sides, front, back and top of the fire-pot and combustion cham-,

ber of horizontal tubes connected by short vertical tubes having fused mitre joints with the horizontal tubes. In the construction shown, the tubes are so arranged as to form four separate circuits.

Referring particularly to Figs. 1 and 4, it will be seen that the front of the firepot is formed by the horizontal tubes 14 which are closely spaced and are connected by the short vertical tubes 15, the joints being mitred and fused as hereinbefore described. A longer vertical tube 16 extends up at one side and is connected, by a similar joint to those already described, with one end of the front tube of the series of horizontal tubes 17 forming the top of the combustion chamber, a spacer 25 supports the outer end of this tube from the lower tube 14. These horizontal tubes are connected by the short horizontal tubes 18 as shown.

The water inlet is indicated at the right hand side of the bottom horizontal tube at the front and the outlet at the left hand side of the rear horizontal tube at the top.

The back of the firepot and combustion chamber is formed by the horizontal tubes 19 which are connected by means of short vertical tubes 20, the joints being as hereinbefore described. The lower three tubes forming the back of the firepot are closely spaced as shown, while the tubes forming the back of the combustion chamber are preferably somewhat more Widely spaced. The inlet is indicated at the bottom and the outlet at the top on the same side.

Each side of the firepot and combustion chamber is formed of a. series of horizontal tubes 21 connected by short vertical tubes 22 by means of joints as hereinbefore described. The spacing of these tubes will follow the spacing of the tubes of the back. Four separate water heating circuits are thus provided. It will be understood, of course, that I do not restrict my self to this arrangement.

At the bottom of the firepo t is located a grate 23 of any suitable construction. Above the top of the combustion chamber I locate a baffle plate 2% of firebrick or other suitable heat resisting material. This prevents the too rapid escape of the products of combustion through the top of the combustion chamber and also serves to distribute the products of combustion around the sides of the under part of the top. Ample contact is thus provided between the products of combustion and the interior of the furnace casing to heat the air passing through the air jacket.

Owing to the extensive heating surface for the water which I provide and owing to the natural direction of the circulation of the water and the freedom of the interior of the pipes from friction creating projeotions, the thermal efliciency of the fur nace is high. It is evident that the same construction of firepot and combustion chamber may be employed if desired to generate steam.

What I claim as my invention is 1. In a furnace, a rectangular fire pot having its sides formed of a plurality of closely spaced horizontal cylindrical tubes and short vertical tubes having fused mit red joints with the horizontal tubes; a rectangular combustion chamber over the fire pot having an open front, the sides and back being formed of spaced horizontal cylindrical tubes and short vertical tubes having fused mitred connections with the horizontal tubes; and a top formed of spaced horizontal cylindrical tubes and short horizontal connecting tubes having fused mitred joints with the aforesaid tubes,

2. In a furnace, the combination of a casing; a rectangular fire pot suitably supported in the casing and having its sides formed of tubes closely set; and a rectangular combustion chamber over the lire pot having its sides and top formed of tubes less closely set and arranged to form a fuel opening at one side, the tubes of both. fire pot and combustion chamber being arranged to provide a continuous horizontal and upward flow only for fluid within the tubes, the tubes of the front of the fire pot and the top of the combustion chamber forming one Water circuit, the tubes of one side of the fire pot and combustion chamher a second circuit, the tubes of the other side of the fire pot and combustion cham her a third circuit, and the tubes of the back of the fire pot and combustion chamber a fourth circuit.

Signed at Toronto, Canada, this 12th day of May 1922.

AUBREY EDWARD STREADWICK. 

